Water, ink volume and the expansion of outlets

On the offset printing press, the inking device not only applies ink to the printed image, but also performs other functions such as ink distribution to improve the performance of the ink and to receive the wetting liquid to emulsify the ink. The above factors will affect the expansion of outlets. The thicker the ink layer provided by the ink roller system, the more non-directional dots are expanded.

The wetting system applies a water-based wetting fluid to the printing plate, which functions to quickly and completely separate the image and non-image portions of the plate. The operator must maintain a balance between water supply and ink supply. Too much water may cause the viscosity of the ink to decrease, thereby increasing the dot gain.

Although electronic prepress technology, laser graphic output technology, and optical density measurement technology provide some means for the control of dot gains, the complexity of the lithographic printing process and the ever-changing technological changes will still bring printing trouble to the printers. Understanding how dot gains occur, where they occur, and how they are controlled will certainly help printers get high-quality prints.

Source: PACK.CN